/*
 * Copyright (c) 2017 Jacob Rachiele
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
 * and associated documentation files (the "Software"), to deal in the Software without restriction
 * including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense
 * and/or sell copies of the Software, and to permit persons to whom the Software is furnished to
 * do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all copies or
 * substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED
 * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
 * PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 * USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 * Contributors:
 *
 * Jacob Rachiele
 */

package com.github.signaflo.math.optim;

import com.github.signaflo.math.linear.doubles.Vector;
import com.github.signaflo.math.function.AbstractMultivariateFunction;
import org.junit.Test;

import static org.hamcrest.MatcherAssert.*;
import static org.hamcrest.Matchers.*;

public class QuasiNewtonLineFunctionSpec {

    @Test
    public void whenAbstractMultivariateFunctionThenComputedProperly() {
        AbstractMultivariateFunction f = new RosenbrockFunction();
        Vector point = Vector.from(2, 3);
        Vector searchDirection = Vector.from(1, -1);
        QuasiNewtonLineFunction lineFunction = new QuasiNewtonLineFunction(f, point, searchDirection);
        double result = lineFunction.at(0.5);
        assertThat(result, is(f.at(point.plus(searchDirection.scaledBy(0.5)))));
    }
}
